GF-EJ-CUMMINS-4BT Swap Block Mock-Up Engine Block, Cummins 3.9 4BT
InfoVehicle Info Needed
G FORCE PERFORMANCE PRODUCTSPART NUMBER: 472-GF-CUMMINS4B

GF-EJ-CUMMINS-4BT Swap Block Mock-Up Engine Block, Cummins 3.9 4BT

$33499
ShippingShips on Sep 14, 2026
Lowest PriceLowest Price Guarantee

Dodge
Swap Block Mock-Up Engine Block
  • Cummins 3.9 4BT
  • Accurate & Rigid Representation of Actual Engine Block
  • Durable Steel Construction
  • Unique Tab-and-Slot Design
  • Resists Welding Heat
  • Includes Hardware

    G Force Performance GF-EJ-CUMMINS-4BT Features:

    • Engine: Cummins 3.9 4BT
    • Years: 1989-1998
    • G Force patent-pending tab-and-slot version of the mock up block provides accurate mounting positions of engine accessories and bolt-ons.
    • Weighs only 26 lbs
    • This unique design is lightweight and comes disassembled for ease of shipping and storage.
    • Precision formed returns on all weight-bearing components and tight tolerance slots create a rigid and accurate representation of the Cummins 4BT 3.9L engine block compared to bolt-together types.
    • One tool accomplishes accurate placement of a 4BT Cummins engine into the chassis build of your choice.
    • Easily positioned by hand, the days of slinging an engine on a crane in and out of your build are over.
    • It's designed to bolt to your transmission while also permitting the attachment of oil pan, motor mounts, header, front timing cover, oil filter housing, and intake.
    • Save time and money and work more safely.
    • Durable steel construction resists heat from welding, so unlike foam blocks, custom motor mounts can be fabricated right on the block.
    • Comes with hardware for exhaust, motor mounts, bellhousing, oil pan, and timing cover.

    NOTE: The 4BT was used in commercial vehicles and industrial applications, so some variations to bolt patterns may be seen. 

    This video shows how to assemble the LS version of our Swap Block Engine Mock Up Blocks. Assembly with G Force patent pending tab and slot system is the same for all of our Swap Blocks.

  • Part TypeMock-Up Engine Block
    BrandG FORCE PERFORMANCE PRODUCTS
    Package Height4.0
    Package Width18.0
    Package Length24.0
    Weight28.0 PG
    Part CategoryPerformance Parts
    Part FitmentSemi Universal
    Vendor Part NumberGF-EJ-CUMMINS-4BT
    Package Qty1
    Package TypeEA
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